Clutch actuated bumper jack



June 1967 TSUNEO TAKEUCHI ETAL. 3,326,526

CLUTCH ACTUATED BUMPER JACK Filed May 20, 1965 'INVENTOR UCHI ll 0R1 SEII CHI ATTORNEY United States Patent 3,326,526 CLUTCH ACTUATED BUMPER JACK Tsuneo Takeuchi, 1 l-chome, KiyokaWa-cho, and Seiichi Hori, 6 l-chome, Norikoe-cho, both of Nakagawa-ku, Nagoya, Aiclii Prefecture, Japan Fiied May 20, 1965, Ser. No. 457,313 Claims priority, application Japan, Sept. 30, 1964 (utility model), 39/77,084 4 Claims. (Cl. 254-166) This invention relates to jacks, and more particularly to bumper jacks for raising weights, such as bodies of vehicles. It is relatively easy to raise heavy weights, but it is not so easy as one might think to safely and positively lower the weights that have been elevated to certain heights so that the objects may be restored to the original position without a hitch. This is what one often experiences in raising bodies of vehicles for repair. It has not been rarely the case that, due to the imperfect mechanism of jacks of the conventional type, one meets with an unexpected accident, suffen'ng injuries caused by the bodies of vehicles dropping down with a rush.

The object of this invention is to provide a bumper jack to facilitate the raising and lowering of heavy weights. by means of a pair of complementary claw members movably disposed along a jack stanchion which are arranged so as to be simultaneously actuated whereby one of said claw members effects a holding action to support the load on the stanchion as the other is released to advance the weight along the jack stanchion in either raising or lowering the load accordingly.

The invention is illustrated in the drawings in which the corresponding numerals refer to the same part in which:

FIG. 1 is a front elevation of a bumper jack of this invention;

FIG. 2 is a back elevation of FIG. 1;

FIG. 3 is a side elevation of FIG. 1, with certain parts broken away;

FIG. 4 illustrates enlarged plan views of certain parts of a bumper jack of this invention; and

FIG. 5 is a view in explanation of the manner in which a bumper jack of this invention is put to use.

In the drawings, the numeral 1 is a column or stanchion supported by a foundation plate or base 2; the numeral 3 is a caseor slider housing formed to provide in the front end thereof a lug 4 for hitching a bumper or other suitable part of .a vehicle thereon and adapted to be elevated and lowered along the column or stanchion 1,

said case or housing 3 having a slit or slot 5 formed in the rear end thereof; the numerals 6 and 7 are holes provided in the upper and lower walls of said case or slider housing 3 respectively through which the column 1 extends;

the numerals 8 and 9 are upper and lower claw plates ,which have annular holes of the same diameter through which the column 1 extends, the upper opening 8' and the lower opening 8" of the hole in the upper claw plate 8 and the upper opening 9 and lower opening 9" of the hole in the lower claw plate 9 being of the same diameter but eccentric to each other; the numeral 10 is a changeover lever attached to the rear part of the upper claw plate ,9 and adapted for switching from raising to lowering operation and vice versa, and said lever 10 being guided in the slit 5; the numeral 11 is a roller rotatably 3,326,525 Patented June 20, 1967 carried by the lower claw plate 9; the numeral 12 is a cam lever pivotally carried at 12 by the case 3; the numeral 13 is a spring connecting said cam lever 12 with the changeover lever 10, and the numerals 14 and 15 are springs.

To explain the structure of a bumper jack of this invention in detail, a case 3, adapted to be elevated and lowered along the column 1 supported by the foundation plate 2, is slidably mounted on said column, said column extending through the holes 6 and 7 formed in the upper wall and the lower wall respectively of said case 3. The case 3 is formed to provide a lug 4 in the front end thereof, and has a slit 5 in the rear end thereof for guiding a changeover lever 10. There are mounted in said case 3 an upper claw plate 8 and a lower claw plate 9 which are positioned one above the other, with the upper claw plate being movably supported in the front end of the case 3 by some suitable means. Springs 14 and 15 encircle the column 1, with spring 14 being mounted between the upper and lower claw plates and spring 15 being mounted between the lower claw plate and the lower wall of the case 3. Both the upper and lower claw plates 8 and 9 have annular holes through which the column 1 extends, the upper opening 8' and the lower opening 8" of the hole in the upper claw plate 8 and the upper opening 9 and the lower opening 9" of the hole in the lower claw plate being of the same diameter but eccentric to each other. On the rear part of the upper claw plate 8 is pivotally mounted a changeover lever 10 which is connected by a spring 13 with a cam lever 12 which is pivotally carried at 12' by the case 3. A roller 11 is rotatably carried by the lower claw plate 9 at the rear end thereof in such a manner that said roller 11 keeps contact with the lower edge of the cam lever 12 at all times.

It will be appreciated from the description of the structure that the edges of the upper and lower openings 8 and 8" of the hole in the upper claw plate 8 and the upper and lower openings 9' and 9" of the hole in the lower claw plate 9 bear against and stick fast to the column 1 which extends therethrough, as said claw plates 8 and 9 are raised or lowered by the forces of springs 14 and 15, so that the case 3 does not sway in its elevati-onal movement. Consequently, when a weight, such as the body of a vehicle w is supported by hitching the bumper b on the lug 4 as shown in FIG. 5, a force which is proportional to the load applied is brought to bear on the front end of the upper claw plate 8 by the case 3, so that the forces with which the upper opening 8' and the lower opening 8" of the hole in the upper claw plate 8 bear against the column 1 diagonally are increased in tensity, thereby supporting the load more positively. In raising a weight, the changeover lever 10 is set to a down position, and the cam lever 12 is pushed down as shown by the arrow in the solid line by means of a lever a mounted on the lever 12. A force is transmitted through the lower edge of the cam lever 12 which is in contact with the roller 11 to the lower claw plate 9, causing the edges of the upper opening 9' and lower opening 9" of the hole therein to bear against and stick fast to the column 1 with greater forces. No sooner has this happened than the case 3 is raised by the cam lever 12 due to the lever principle in which the touching point of the lower edge of said cam lever 12 with the roller 11 forms a fulcrum. When the lever 12 is released, the lever 12 and the lower claw plate 9 are restored to their original positions relative to the casing in the new raised position thereof by the force of spring 15. If this process is repeated, the end of raising a weight can be accomplished. In doing so spring 13 exerts little force on the upper claw plate 8 when the changeover lever 10 is set to a down position when raising the weight.

In lowering a weight, the changeover lever 10 is pivoted upwardly and guided in the slit so that it may be set to an up position, as shown in phantom in FIG. 3. Pushing down the cam lever 12 causes, as in the process described hereinabove for raising a Weight, a force to be transmitted to the lower claw plate 9 through the lower edge of the cam lever 12 which is in contact with the roller 11 mounted on the rear end of the lower claw plate 9, causing the upper opening 9' and lower opening 9" of the hole therein to bear against and stick fast to the column 1 with greater forces, thereby tending to raise the case 3 a little distance. In the next instant, however, a force is transmitted through spring 13 to the rear end of the upper claw plate 8 which is supported at the front end thereof by the case 3, so that the contact of the upper opening 8 and lower opening 8 of the hole in the upper claw plate 8 with the column is loosened by said force, resulting in a state of no load and in lowering the upper claw plate 8 and therefore case 3 by said force in opposition to the force of spring 14. As soon as the case 3 is lowered, the cam lever 12 is restored to the original position by the forces of spring 13, and the lower claw plate 9 is then lowered by the force of spring 14 in opposition to that of spring 15. Thus, pushing down the lever 12 several times causes a weight to be lowered gradually without jolts. The proper operation of changeover lever and cam lever 12 makes it possible to raise or lower a weight to or from a desired :height safely, positively and rapidly. The bumper 'jack of this invention is simple in construction, light in weight and low in cost. The simple construction facilitates assembly, and the solidness of structure makes for easy handling and care. These advantages offered by a bumper jack of this invention make it an ideal tool for raising weights.

What we claim is:

1. A bumper jack comprising a column 1, a foundation plate 2 supporting said column, a case 3 formed to provide a lug 4 in the front end thereof and adapted to be raised and lowered in sliding motion along said column, an upper claw plate 8 and a lower claw plate 9 mounted one above the other in said case, said plates having holes therein through which said column extends, the upper opening 8' and lower opening 8" of the hole in the upper claw plate 8 and the upper opening 9' and lower opening 9" of the hole in the lower claw plate being of the same diameter but eccentric to each other, and said upper claw plate being movably supported by said case, springs 14 and mounted between the upper claw plate and the lower claw plate and between the lower claw plate and the lower wall of said case respectively, a changeover lever 10 pivotally carried by the upper claw plate at the rear part thereof and guided in the slit 5 formed in the rear end of said case, a cam lever 12 carried at 12' by said case and a roll 11 r-otatably carried by the lower cl-aw plate at the rear end thereof, said changeover lever and said cam lever being connected with each other by a spring 13 and the lower edge of said cam lever being in contact with said roller at all times.

2. A device for raising and lowering a load in a gradual manner comprising:

(a) an upright stanchion,

(b) means for supporting said stanchion,

(c) means for supporting a load slidably mounted on said stanchion,

(d) means for providing incremental displacement of said load supporting means along said stanchion to raise and lower the load accordingly,

(e) said latter means including upper and lower complementary claw means only which are alternately actuated so that one of said complementary means effects a holding action as the other of said means is released to advance said lead along said stanchion in a given direction,

(f) actuating lever means simultaneously operating on each said pair of complementary means to effect sequential alternate actuation thereof, for either raising or lowering said load along said stanchion whereby one of said pair of complementary claw means effects a holding action as the other claw means is released to effect advancement of said load supporting means along said stanchion,

g) a changeover lever pivotally connected to said upper claw means to change the direction in which said load is advanced along said stanchion, and a spring means operatively connected between said changeover lever and said actuating lever means.

3. A device for raising and lowering a load comprising:

(a) a stanchion,

(b) means for supporting said stanchion in an upright position,

(c) a hollow slider having a means projecting therefrom for supporting a load to be raised or lowered,

(d) means disposed within said slider for providing incremental displacement of said slider and load supported there-on along said stanchion,

(c) said latter means including an upper and lower claw member, each having an aligned bore extending therethrough for receiving said stanchion,

(f) the bore in each of said claw members having a top and bottom opening eccentrically disposed relative to each other to permit limited skewing of said claw member relative to said stanchion,

(g) 'said upper claw member being supported within said slider,

(h) a spring disposed between said claw members,

(i) and a second spring disposed between said second claw member and said slider,

(j) means including a cam lever pivotally connected to said slider simultaneously acting on said claw members for effecting alternate operation of said claw members whereby one of said claw members effects a holding action and the other is released to advance along said stanchion for incrementally advancing said slider and load along said stanchion accordingly,

(k) and a changeover means operatively connected with said cam lever for effecting a change in the direction in which said load advances along said stanchion,

(l) and a spring means interconnected between said cam lever and said changeover lever.

4. A jack for raising and lowering a load comprising:

(a) a stanchion,

(b) means for supporting said stanchion in an upright position,

(0) a slider casing having a means projecting therefrom for supporting a load, ((1) said casing having aligned openings formed therein through which said stanchion extends,

(e) means disposed within said' casing for providing incremental displacement of said casing and load along said stanchion,

(f) said latter means including an upper and lower claw plate,

(g) each of said claw plates having a bore extended therethrough through which said stanchion extends,

(h) each of said bores having its opening in the top and bottom of its respective plate eccentrically disposed to permit limited skewing of said respective plate relative to said stanchion to effect a holding force,

(i) means securing said upper claw plate to said casing for relative limited movement thereto,

(j) a spring means interposed between said claw plates,

(k) and a second spring disposed between said lower claw plate and said casing,

(l) a changeover lever pivotally connected to said upper claw plate,

(In) a roller connected to said lower claw plate,

(11) a cam lever operating on said roller to effect alternate actuation of said claw plates to efiect incremental movement of said casing and load along said stanchion,

(o) and a spring means interconnecting said changeover lever to said cam lever.

References Cited UNITED STATES PATENTS FOREIGN PATENTS 12/1951 Germany.

OTHELL M. SIMPSON. Primary Examiner. 

1. A BUMBER JACK COMPRISING A COLUMN 1, A FOUNDATION PLATE 2 SUPPORTING SAID COLUMN, A CASE 3 FORMED TO PROVIDE A LUG 4 IN THE FRONT END THEREOF AND ADAPTED TO BE RAISED AND LOWERED IN SLIDING MOTION ALONG SAID COLUMN, AN UPPER CLAW PLATE 8 AND A LOWER CLAW PLATE 9 MOUNTED ONE ABOVE THE OTHER IN SAID CASE, SAID PLATES HAVING HOLES THEREIN THROUGH WHICH SAID COLUMN EXTENDS, THE UPPER OPENING 8'' AND LOWER OPENING 8" OF THE HOLE IN THE UPPER CLAW PLATE 8 AND THE UPPER OPENING 9'' AND LOWER OPENING 9" OF THE HOLE IN THE LOWER CLAW PLATE BEING OF THE SAME DIAMETER BUT ECCENTRIC TO EACH OTHER, AND SAID UPPER CLAW PLATE BEING MOVABLY SUPPORTED BY SAID CASE, SPRINGS 14 AND 15 MOUNTED BETWEEN THE UPPER CLAW PLATE AND THE LOWER CLAW PLATE AND BETWEEN THE LOWER CLAW PLATE AND THE LOWER WALL OF SAID CASE RESPECTIVELY, A CHANGEOVER LEVER 10 PIVOTALLY CARRIED BY THE UPPER CLAW PLATE AT THE REAR PART THEREOF AND GUIDED IN THE SLIT 5 FORMED IN THE REAR END OF SAID CASE, A CAM LEVER 12 CARRIED AT 12'' BY SAID CASE AND A ROLL 11 ROTATABLY CARRIED BY THE LOWER CLAW PLATE AT THE REAR END THEREOF, SAID CHANGEOVER LEVER AND SAID CAM LEVER BEING CONNECTED WITH EACH OTHER BY A SPRING 13 AND THE LOWER EDGE OF SAID CAM LEVER BEING IN CONTACT WITH SAID ROLLER AT ALL TIMES. 